Multiple v-belt drive for a crowd mechanism of a power shovel

ABSTRACT

Crowd driving mechanism for the dipper stick of a power shovel, and also including a multiple V-belt and means for tensioning the same. An air supply inside the boom for cooling the belt and motor.

United States Patent Charles R. Siegel Cudahy;

Karl Schneider, Greenfield, Wis. 818,64 1

Apr. 23, 1969 May 25, 1971 l-larnischfeger Corporation Milwaukee, Wis.

Inventors Appl. No. Filed Patented Assignee MULTIPLE V-BELT DRIVE FOR A CROWD MECHANISM OF A POWER SHOVEL 19 Claims, 9 Drawing Figs.

US. Cl... 214/135 Int. Cl 1502i 3/00 Field of Search 214/135,

[56] References Cited UNITED STATES PATENTS 832,370 10/1906 Ford 214/135 1,610,502 12/1926 Fairbanks et al. 214/135 2,315,781 4/1943 Gerow 214/135 2,766,417 10/1956 Merritt 74/242.8X 3,146,843 9/1964 Hinson et al 74/242.8X

Primary Examiner-Gerald M. Forlenz Assistant ExaminerFrank E. Werner Attorney-James E. Nilles ABSTRACT: Crowd driving mechanism for the dipper stick of a power shovel, and also including a multiple V-belt and means for tensioning the same. An air supply inside the boom for cooling the belt and motor.

MULTIPLE V-BELT DRIVE FOR A CROWD MECHANISM OF A POWER SIIOVEL BACKGROUND OF THE INVENTION The invention pertains generally to power shovels having a boom on which a dipper stick is mounted for pivoting about and sliding therewith, the dipper stick having a dipper at its lower end. The dipper stick is mounted for movement relative to the boom so that the dipper can be crowded into the material. Various prior art mechanisms have been proposed for forcing the dipper stick and the dipper into the work commonly referred to as crowd drive mechanisms. These mechanisms in the past have taken various forms such as sprockets chain as shown in the U.S. Pat. No. 2,080,163 issued May 11, 1937; the crowd belt as shown in the U.S. Pat. No. 2,304,486, issued Dec. 8, 1942; a hydraulic crowd mechanism as shown in U.S. Pat. No. 1,937,432 issued Nov. 28, I933; a cable drive mechanism as shown in U.S. Pat. No. 2,380,625 of July 3l, 1945; or a chain drive mechanism as shown in the U.S. Pat. No. 1,536,609 of May 5,1925.

These prior art devices, as well as other types such as the straight spur gear, bevel gear, or worm wheel drives were unsatisfactory for one reason or another. For example, some of them employed a solid connection between the motor and transmission and high shock loads caused damage to the parts. Attempts were made to solve these problems by making the parts unusually heavy orby interposing slip clutches in the drive mechanism, which clutches must be carefully set. The use of torque shafts or tubes is another means of absorbing energy in the prior art devices.

SUMMARY OF THE INVENTION The present invention provides a crowd drive mechanism for the dipper stick of a power shovel, which mechanism includes a multiple V-belt for trasmitting power from an electric motor to a gear reduction unit that in turn drives the shipper shaft of the dipper stick.

Another aspect of the present invention relates to means for tensioning the V-belt, and also for measuring the proper tension thereof.

Another aspect of the invention relates to an air supply means built within the boom to supply filtered air to cool the motor and belt.

These and other objects and advantages of the invention will appear hereinafter as this disclosure progresses, reference being had to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a power shovel embodying the present invention;

FIG. 2 is a perspective view of the boom shown in FIG. I, and showing the drive mechanism thereon;

FIG. 3 is an enlarged, spread-out view of the gear reduction mechanism between the multiple V-belt and the shipper shaft;

FIG. 4 is a side elevational view of the drive mechanism shown in FIG. 1, but on an enlarged scale;

FIG. 5 is a view taken generally along the line 5-5 in FIG. 4, certain parts being shown in section or removed for the sake of clarity in the drawings;

FIG. 6 is a side elevational view of the inner side of the belt housing shown in FIG. 4;

FIG. 7 is an elevational view of the adjusting nut assembly shown in FIG. 4;

FIG. 8 is a sectional view taken along line 8-8 in FIG. 4, but on an enlarged scale, and showing a portion of the tensioning device; and

FIG. 9 is a perspective view of the air supply and filtering means.

LII

DESCRIPTION OF THE PREFERRED EMBODIMENT The general organization of a power shovel embodying the present invention is shown in FIG. 1 and includes a revolvable upper frame I mounted on the groundengaging means 2, which means has been shown as endless tracks. A boom 3 extends from the upper revolvable part from its mounting 4. The boom is suspended by the conventional cables 5 and has a large sheave 6 at its outer end. The hoist cable 7 extends over the sheave from the winch drum 8 and is fastened to the dipper 9. The dipper 9 is fixed to the end of a dipper stick 10, the latter in turn being mounted for movement on and relative to the boom 3. By extending the dipper stick 10 relative to the boom, a crowding action of the dipper into the material (not shown) is accomplished. The means for so driving the dipper stick l0 outwardly, and also for retracting it inwardly, is known as the crowd drive mechanism and specific reference will now be made to this mechanism.

Referring to FIG. 3, the dipper stick 10 is comprised of two sticks 10a and 10b which are spaced apart but rigidly fastened together at their lower ends to form a unitary dipper stick. The rear sides of these dipper sticks have a gear rack 12 formed therealong and these gear racks are in constant mesh with the spur gears 14 fixed on the shipper shaft 15. The shipper shaft 15 is suitably journaled in the boom 3 in the known manner and rotation of this shipper shaft 15 in one direction or another causes extension or retraction of the dipper stick 10. Also secured to the shaft 15 is a central gear 17 which is in constant mesh with the pinion 18 which is an integral part of lay shaft 19. The lay shaft 19 is suitably journaled in the boom 3 and has another, larger spur gear 20 fixed thereto. Spur gear 20 in turn is in constant mesh with the pinion 21 which may be formed as an integral part of shaft 22, the shaft 22 in turn also being suitably journaledin the boom 3.

MULTIPLE, V-BELT DRIVE One end of the shaft 22 has a multiple V-pulley 25 secured thereto. An electric motor 30 is also mounted on the boom 3 and it has a multiple V-pulley 31 (FIG. 5) fixed to its shaft 32.

An endless multiple V-belt 33 is trained over the pulleys 25 and 31. A V-belt in which at least two of the individual V-belts are made as an integral part, has been found to be particularly advantageous in a drive of this type, because lateral movement or twisting of this belt does not then occur. Other numbers of individual belts can be made as one, and in the embodiment shown, the entire belt is of unitized construction, which has proven to be very advantageous.

The electric motor, through the unitized, multiple V-belt, drives the gear reduction mechanism and consequently, the shaft 15. This arrangement provides the necessary power transmission and also a very convenient and effective location of the driving motor 30. It also provides a very effective slip means to absorb the high shock loads during digging operations.

BELT TENSIONING MEANS Means are provided for insuring that proper tensioning is applied to the belt, which is important because, for one thing, over tensioning of the belt prevents its ability to slip when overloaded and also results in undue belt wear, and ruining the electric motor bearings at the pulley end. This means for properly tensioning the belt will now be described.

The electric motor is secured to a base 40 which in turn has two depending, bifurcated brackets 42 and 44 (FIGS. 4 and 5) which are pivotally mounted to upstanding members 45 and 46 respectively, by means of the pivot pins 48. Adjusting means are provided for tilting the motor and its base about the pins 48, in one direction or another, so as to vary the amount of tension in the unitized, endless multiple V-belt 33. This adjusting means includes a large I-bolt 50 which is pivoted at its lower end to the pin 51 fixed on the boom 3. An adjusting collar nut assembly 52 (FIG. 7) is threadably mounted on the I- bolt and a jam nut 54 is also threaded on the l-bolt for locking the assembly 52 in its adjusted position. The assembly 52 is rotatably mounted in the open ended bracket 55 (FIG. 3) fixed on the base 40.

By rotating the assembly 52 on its shaft 50, the motor is caused to swing about the pivot axis 48, in one direction or another, depending on the direction in which the assembly 52 is adjusted, to thereby properly set the tension in the V-belt. When assembly 52 is rotatably adjusted, it can also slide in the open ended, or bifurcated bracket 55. This accommodates the swinging movement of the bracket.

BELT TENSION MEASURING DEVICE A tension measuring device 60 (FIGS. 4 and 8) is located midway between the driver pulley 31 and the driven pulley 25, and is used to measure the play in the belt so that the base 40 can be adjusted accordingly. This measuring device includes a horizontally disposed roller 65 which is journaled in sleeve bearing 66 on shaft 67. The shaft 67, in turn, is mounted in the bracket 68 that has a tube 69 fixed, as by welding, thereto and extending downwardly therefrom. An upward extending tube 70 concentric with tube 69 and receiving it for telescoping relationship, is welded at its lower end to a base 72. The base 72 in turn, is pivotally mounted by stub shafts 73 which are mounted in the pillow block bearings 74 fixed on the boom 3. A threaded bolt 75 is welded at its upper end to bracket 68 and extends downwardly through the tubes. A nut 76 is threadably engaged on the lower end of bolt 75, thereby limiting the extension of the tubes 69 and 70. A spring 79 is located within the tubes and acts to normally bias the tubes 69 and 70 in the extended direction, which forces the roller 65 against the underside of the multiple V-belt 33.

A detent 80 is also fixed to the boom 3 and when the above described telescopic and spring loaded tensioning device is not is use, as when the belt is being driven, the roller 65 can drop the detent 80 and be firmly held therein.

When the spring-loaded tensioning device is to be used, (when the belt is not moving) the spring 79 is compressed and the device is swung to the position shown in FIG. 4. The roller 65 aids in this positioning against the belt. An annular market or groove 82 is provided on the tube 69 and when this groove or marker 82 is in alignment with the upper end of the tube 70, the correct belt tension has been obtained for a new belt. A

similar groove 83 is provided lower down on the tube to mark the correct position of the pivoted motor when the belt has been run-in for a predetermined time.

AIR SUPPLY MEANS An airsupply means is provided for furnishing filtered air to both the motor 30 and the V-belt 33 so as to cool these parts and prevent them from being overheated. This air supply means is built within the boom in a compact manner and is particularly efiicient in cooling the parts and thereby prolonging their life. This air supply means will now be described in detail.

An air blower B having a supply motor 90 is suspended within the boom and takes in air through the inlet 91 and delivers it through the filter section F of the duct work 92 which is suspended by hangers 93 from the upper portion of the boom. As the air passes through the filtering vanes 94 of the filtering unit, the foreign material is caused to drop into the discharge duct 95 and is expelled through the discharge opening 96 (FIGS. 2, 4 and 9) in the side of the boom. A certain portion of the air is forced from the filtering unit through the duct 97 in the boom and then through the flexible and expansible connector 9% where it is then discharged past the motor 30. Air is also discharged from the filtering unit through another duct 99 and then into duct 100 from which the air then discharges into the housing H which encloses the V-belt drive. The air, after cooling the V-belt is then discharged through the discharge opening 101 of the housing.

Referring now to the housing H, it includes an outer side 102 which is mounted by hinges 1103 so that it can be swung outwardly for inspection, repair or replacement of the V-belt unit. The housing also includes an inner side I05 having an opening 106 through which the motor shaft extends. In order to maintain the housing enclosed, even though the motor and its shaft are shifted relative to the housing, a sliding plate 108 is mounted in an upper bracket I09 and a lower bracket 110 which are fixed to the side of the housing. In this manner, as the belt is tensioned properly due to shifting of the motor 30 and its base 40, the sliding plate 108 which slides with the motor shaft, always maintains the housing opening 106 substantially closed.

The housing H also includes the peripheral wall 112 which extends all around the housing. The housing H is secured by bolts 1 M to the upper portion of the boom 3.

In this manner, a compact air supply arrangement is provided which insures a continual supply of filtered air to both the belt and the motor. The supply mechanism is located out of the way and contributes greatly to increased life of the various parts.

We claim:

I. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, a gear fixed to said shaft, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said gear on said shaft for rotating said shaft, an electric motor secured to said boom, and multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other to thereby shift said stick.

2. The shovel as defined in claim ll including means for adjusting the position of said motor relative to said boom to vary the tension of said multiple V-belt means.

3. The shovel as set forth in claim 2 including a motor base shiftably mounted on said boom, said motor being secured to said base, and adjustment means between said base and boom for shifting said base to thereby vary the position of said motor and consequently the tension of said multiple V-belt means.

4. The shovel set forth in claim 1 including air supply means mounted in said boom for supplying cooling air to said motor and multiple V-belt means.

5. The arrangement as described in claim 4 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge adjacent said motor and multiple V-belt means.

6. The combination set out in claim 5 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.

7. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said shaft for rotating said shaft, a motor base shiftably mounted on said boom, an electric motor secured to said base, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other to thereby shift said stick, adjustment means between said base and boom for rotating said base to thereby vary the position of sad motor and consequently the tension of said multiple V-belt means, and air supply means mounted in said boom for supplying cooling air to said motor and multiple V- belt means.

8. The arrangement as described in claim 7 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge adjacent said motor and multiple V-belt means.

9. The combination set out in claim 8 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.

10. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said shaft for rotating said shaft, a motor base shiftably mounted on said boom, an electric motor secured to said base, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other to thereby shift said stick, an enclosing housing secured to said boom and enclosing said V-belt means and said pulley means, adjustment means between said base and boom for shifting said base to thereby vary the position of said motor and consequently the tension of said multiple V-belt means; and air supply means mounted in said boom and including an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means including flexible duct means between said boom and said motor, said duct means having a discharge adjacent said motor and multiple V- belt means for supplying cooling air thereto.

11. A boom for a power shovel and having a shipper shaft thereon, said boom having crowd drive mechanism mounted thereon, said mechanism including reduction gearing in driving connection with said shaft for rotating said shaft, an electric motor secured to said boom, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other and air supply means mounted in said boom for supplying cooling air to said motor and multiple V-belt means.

12. The arrangement as described in claim 11 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge ad jacent said motor and multiple V-belt means.

13. The combination set out in claim 12 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.

14. A power shovel having a swingable boom, a shipper shaft joumaled on said boom intermediate the length of said boom, crowd drive mechanism mounted on said boom and in driving connection with said shaft, said mechanism including an electric motor secured to said boom and an endless unitized multiple V-belt means and pulley means connected to said motor, and a tension measuring device to measure looseness in said V-belt means and including a telescoping strut pivotally secured to said boom and having a free end engageable with said belt, said strut having means for resiliently urging said free end against said belt, and marker means on said strut to visually determine the extent of strut extension and consequently, the looseness of said V-belt means.

15. The apparatus of claim 14 further characterized in that said strut free end has a roller rotatably mounted thereon for engagement with said V-belt means.

16. The device of claim 14 including a detent fixed to said boom and adapted to hold said strut when the latter is swung from said V-belt means.

17. In a power shovel having a boom and a crowd drive mechanism mounted on said boomand including an endless unitized multiple V-belt means, a tension measuring device to measure looseness in said V-belt means and including a telescoping strut ivot ally secured to said boomand having a free end engagea le with said belt, said strut having means or resiliently urging said free end against said belt, and marker means on said strut to visually determine the extent of strut extension and consequently the looseness of said V-belt means.

18. The apparatus of claim 17 further characterized in that said strut free end has a roller rotatably mounted thereon for engagement with said V-belt means.

19. The device of claim 17 including a detent fixed to said boom and adapted to hold said strut when the latter is swung away from said V-belt means. 

1. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, a gear fixed to said shaft, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said gear on said shaft for rotating said shaft, an electric motor secured to said boom, and multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other to thereby shift said stick.
 2. The shovel as defined in claim 1 including means for adjusting the position of said motor relative to said boom to vary the tension of said multiple V-belt means.
 3. The shovel as set forth in claim 2 including a motor base shiftably mounted on said boom, said motor being secured to said base, and adjustment means between said base and boom for shifting said base to thereby vary the position of said motor and consequently the tension of said multiple V-belt means.
 4. The shovel set forth in claim 1 including air supply means mounted in said boom for supplying cooling air to said motor and multiple V-belt means.
 5. The arrangement as described in claim 4 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge adjacent said motor and multiple V-belt means.
 6. The combination set out in claim 5 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.
 7. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said shaft for rotating said shaft, a motor base shiftably mounted on said boom, an electric motor secured to said base, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft iN one rotational direction or the other to thereby shift said stick, adjustment means between said base and boom for rotating said base to thereby vary the position of sad motor and consequently the tension of said multiple V-belt means, and air supply means mounted in said boom for supplying cooling air to said motor and multiple V-belt means.
 8. The arrangement as described in claim 7 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge adjacent said motor and multiple V-belt means.
 9. The combination set out in claim 8 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.
 10. A power shovel having a boom, a shipper shaft journaled on said boom intermediate the length of said boom, and a dipper stick shiftably mounted on said boom and having a driving connection with said shaft whereby rotation of said shaft causes shifting of said stick relative to said boom, crowd drive mechanism mounted on said boom and comprising, reduction gearing on said boom and in driving connection with said shaft for rotating said shaft, a motor base shiftably mounted on said boom, an electric motor secured to said base, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other to thereby shift said stick, an enclosing housing secured to said boom and enclosing said V-belt means and said pulley means, adjustment means between said base and boom for shifting said base to thereby vary the position of said motor and consequently the tension of said multiple V-belt means; and air supply means mounted in said boom and including an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means including flexible duct means between said boom and said motor, said duct means having a discharge adjacent said motor and multiple V-belt means for supplying cooling air thereto.
 11. A boom for a power shovel and having a shipper shaft thereon, said boom having crowd drive mechanism mounted thereon, said mechanism including reduction gearing in driving connection with said shaft for rotating said shaft, an electric motor secured to said boom, a unitized multiple V-belt means and pulley means connected between said motor and said reduction gearing whereby said motor rotates said shaft in one rotational direction or the other and air supply means mounted in said boom for supplying cooling air to said motor and multiple V-belt means.
 12. The arrangement as described in claim 11 further characterized in that said supply means includes an air blower in said boom, duct means extending in said boom and connected to said blower, said duct means having a discharge adjacent said motor and multiple V-belt means.
 13. The combination set out in claim 12 including an air filter in said duct means, and a dirty air discharge duct extending from said air filter and outwardly of said boom.
 14. A power shovel having a swingable boom, a shipper shaft journaled on said boom intermediate the length of said boom, crowd drive mechanism mounted on said boom and in driving connection with said shaft, said mechanism including an electric motor secured to said boom and an endless unitized multiple V-belt means and pulley means connected to said motor, and a tension measuring device to measure looseness in said V-belt means and including a telescoping strut pivotally secured to said boom and having a free end engageable with said belt, said strut having means for resiliently urging said free end against said belt, and marker means on said strut to visually determine the extent of strut extension and consequently, the looseness of said V-belt means.
 15. The apparatus of claim 14 further characterized in that said strut free end has a roller rotatably mounted thereon for engagement with said V-belt means.
 16. The device of claim 14 including a detent fixed to said boom and adapted to hold said strut when the latter is swung from said V-belt means.
 17. In a power shovel having a boom and a crowd drive mechanism mounted on said boom and including an endless unitized multiple V-belt means, a tension measuring device to measure looseness in said V-belt means and including a telescoping strut pivotally secured to said boom and having a free end engageable with said belt, said strut having means for resiliently urging said free end against said belt, and marker means on said strut to visually determine the extent of strut extension and consequently the looseness of said V-belt means.
 18. The apparatus of claim 17 further characterized in that said strut free end has a roller rotatably mounted thereon for engagement with said V-belt means.
 19. The device of claim 17 including a detent fixed to said boom and adapted to hold said strut when the latter is swung away from said V-belt means. 